Papers › SeamlessM4T: Massively Multilingual & Multimodal Machine Translation

SeamlessM4T: Massively Multilingual & Multimodal Machine Translation

22 Aug 2023arXiv:2308.11596archive 2025-07-28

Seamless Communication, Loïc Barrault, Yu-An Chung, Mariano Cora Meglioli, David Dale, Ning Dong, Paul-Ambroise Duquenne, Hady Elsahar, Hongyu Gong, Kevin Heffernan, John Hoffman, Christopher Klaiber, Pengwei Li, Daniel Licht, Jean Maillard, Alice Rakotoarison, Kaushik Ram Sadagopan, Guillaume Wenzek, Ethan Ye, Bapi Akula, Peng-Jen Chen, Naji El Hachem, Brian Ellis, Gabriel Mejia Gonzalez, Justin Haaheim, Prangthip Hansanti, Russ Howes, Bernie Huang, Min-Jae Hwang, Hirofumi Inaguma, Somya Jain, Elahe Kalbassi, Amanda Kallet, Ilia Kulikov, Janice Lam, Daniel Li, Xutai Ma, Ruslan Mavlyutov, Benjamin Peloquin, Mohamed Ramadan, Abinesh Ramakrishnan, Anna Sun, Kevin Tran, Tuan Tran, Igor Tufanov, Vish Vogeti, Carleigh Wood, Yilin Yang, Bokai Yu, Pierre Andrews, Can Balioglu, Marta R. Costa-jussà, Onur Celebi, Maha Elbayad, Cynthia Gao, Francisco Guzmán, Justine Kao, Ann Lee, Alexandre Mourachko, Juan Pino, Sravya Popuri, Christophe Ropers, Safiyyah Saleem, Holger Schwenk, Paden Tomasello, Changhan Wang, Jeff Wang, Skyler Wang

What does it take to create the Babel Fish, a tool that can help individuals translate speech between any two languages? While recent breakthroughs in text-based models have pushed machine translation coverage beyond 200 languages, unified speech-to-speech translation models have yet to achieve similar strides. More specifically, conventional speech-to-speech translation systems rely on cascaded systems that perform translation progressively, putting high-performing unified systems out of reach. To address these gaps, we introduce SeamlessM4T, a single model that supports speech-to-speech translation, speech-to-text translation, text-to-speech translation, text-to-text translation, and automatic speech recognition for up to 100 languages. To build this, we used 1 million hours of open speech audio data to learn self-supervised speech representations with w2v-BERT 2.0. Subsequently, we created a multimodal corpus of automatically aligned speech translations. Filtered and combined with human-labeled and pseudo-labeled data, we developed the first multilingual system capable of translating from and into English for both speech and text. On FLEURS, SeamlessM4T sets a new standard for translations into multiple target languages, achieving an improvement of 20% BLEU over the previous SOTA in direct speech-to-text translation. Compared to strong cascaded models, SeamlessM4T improves the quality of into-English translation by 1.3 BLEU points in speech-to-text and by 2.6 ASR-BLEU points in speech-to-speech. Tested for robustness, our system performs better against background noises and speaker variations in speech-to-text tasks compared to the current SOTA model. Critically, we evaluated SeamlessM4T on gender bias and added toxicity to assess translation safety. Finally, all contributions in this work are open-sourced and accessible at https://github.com/facebookresearch/seamless_communication

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add_inference_arguments facebookresearch/seamless_communication/src/seamless_communication/cli/m4t/predict/predict.py official repository ran · our draft was wrong licence not identified · pointer only · 9f6a6a6199e1dc32 · report
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Tasks

Automatic Speech RecognitionMachine TranslationSpeech-to-Speech TranslationSpeech-to-TextSpeech-to-Text TranslationText to SpeechTranslationtext-to-speechtext-to-speech translation

Results from the paper archive 2025-07-28

TaskDatasetModelMetricValueRank at snapshotLeaderboardReport
Machine Translation FLoRes-200 SeamlessM4T-Large-V1 BLEU 37.5 #3 of 5 Archive leaderboard report
Machine Translation flores95-devtest X-eng SeamlessM4T Large ChrF++ 60.8 #1 of 3 Archive leaderboard report
Machine Translation flores95-devtest X-eng SeamlessM4T-NLLB-1.3B ChrF++ 60.7 #2 of 3 Archive leaderboard report
Machine Translation flores95-devtest X-eng SeamlessM4T Medium ChrF++ 55.4 #3 of 3 Archive leaderboard report
Machine Translation flores95-devtest eng-X SeamlessM4T Large ChrF++ 50.9 #1 of 3 Archive leaderboard report
Machine Translation flores95-devtest eng-X SeamlessM4T-NLLB-1.3B ChrF++ 49.6 #2 of 3 Archive leaderboard report
Machine Translation flores95-devtest eng-X SeamlessM4T Medium ChrF++ 48.4 #3 of 3 Archive leaderboard report
Speech-to-Speech Translation CVSS SeamlessM4T Large ASR-BLEU 36.5 #1 of 2 Archive leaderboard report
Speech-to-Speech Translation CVSS SeamlessM4T Large Parameters 2.3B #1 of 2 Archive leaderboard report
Speech-to-Speech Translation CVSS SeamlessM4T Medium ASR-BLEU 28.1 #2 of 2 Archive leaderboard report
Speech-to-Speech Translation CVSS SeamlessM4T Medium Parameters 1.2B #2 of 2 Archive leaderboard report
Speech-to-Speech Translation FLEURS X-eng SeamlessM4T LargeV2 ASR-BLEU 29.4 #3 of 7 Archive leaderboard report
Speech-to-Speech Translation FLEURS X-eng SeamlessM4T Large ASR-BLEU 25.8 #4 of 7 Archive leaderboard report
Speech-to-Speech Translation FLEURS X-eng SeamlessM4T Medium ASR-BLEU 20.4 #7 of 7 Archive leaderboard report
Speech-to-Text Translation CoVoST 2 X-eng SeamlessM4T Large BLEU 34.1 #1 of 2 Archive leaderboard report
Speech-to-Text Translation CoVoST 2 X-eng SeamlessM4T Medium BLEU 29.8 #2 of 2 Archive leaderboard report
Speech-to-Text Translation CoVoST 2 eng-X SeamlessM4T Large BLEU 30.6 #1 of 2 Archive leaderboard report
Speech-to-Text Translation CoVoST 2 eng-X SeamlessM4T Medium BLEU 26.6 #2 of 2 Archive leaderboard report
Speech-to-Text Translation FLEURS X-eng SeamlessM4T Large BLEU 24.0 #1 of 2 Archive leaderboard report
Speech-to-Text Translation FLEURS X-eng SeamlessM4T Medium BLEU 20.9 #2 of 2 Archive leaderboard report
Speech-to-Text Translation FLEURS eng-X SeamlessM4T Large BLEU 21.5 #1 of 2 Archive leaderboard report
Speech-to-Text Translation FLEURS eng-X SeamlessM4T Medium BLEU 19.2 #2 of 2 Archive leaderboard report

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